Intake of different types of dairy and its prospective association with risk of type 2 diabetes: The Rotterdam Study.

BACKGROUND AND AIMS: The prevalence of type 2 diabetes (T2DM) is increasing. Several studies have suggested a beneficial effect of several major dairy nutrients on insulin production and sensitivity. Conversely, harmful effects have been suggested as well. This study aimed to investigate the impact of the full-range of dairy products and its association with incidence T2DM in Dutch adults aged ≥55 years participating in the Rotterdam Study. METHODS AND RESULTS: Dairy intake was assessed with a validated FFQ, including total, skimmed, semi-skimmed, full-fat, fermented, and non-fermented dairy, and subclasses of these product groups. Verified prevalent and incident diabetes were documented. Cox proportional hazards regression and spline regression were used to analyse data, adjusting for age, sex, alcohol, smoking, education, physical activity, body mass index, intake of total energy, energy-adjusted meat, and energy-adjusted fish intake. Median total dairy intake was 398 g/day (IQR 259-559 g/day). Through 9.5 ± 4.1 years of follow-up, 393 cases of incident T2DM were reported. Cox and spline regression did not point towards associations of total dairy consumption, dairy consumption based on fat content, non-fermented or fermented dairy consumption, or individual dairy product consumption with incident T2DM. The HR for total dairy intake and T2DM was 0.93 (95% CI: 0.70-1.23) in the upper quartile (P-for trend 0.76). CONCLUSIONS: This prospective cohort study did not point towards an association between dairy consumption and T2DM.

Consumption of sweet beverages and type 2 diabetes incidence in European adults: results from EPIC-InterAct.

AIMS/HYPOTHESIS: Consumption of sugar-sweetened beverages has been shown, largely in American populations, to increase type 2 diabetes incidence. We aimed to evaluate the association of consumption of sweet beverages (juices and nectars, sugar-sweetened soft drinks and artificially sweetened soft drinks) with type 2 diabetes incidence in European adults. METHODS: We established a case-cohort study including 12,403 incident type 2 diabetes cases and a stratified subcohort of 16,154 participants selected from eight European cohorts participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. After exclusions, the final sample size included 11,684 incident cases and a subcohort of 15,374 participants. Cox proportional hazards regression models (modified for the case-cohort design) and random-effects meta-analyses were used to estimate the association between sweet beverage consumption (obtained from validated dietary questionnaires) and type 2 diabetes incidence. RESULTS: In adjusted models, one 336 g (12 oz) daily increment in sugar-sweetened and artificially sweetened soft drink consumption was associated with HRs for type 2 diabetes of 1.22 (95% CI 1.09, 1.38) and 1.52 (95% CI 1.26, 1.83), respectively. After further adjustment for energy intake and BMI, the association of sugar-sweetened soft drinks with type 2 diabetes persisted (HR 1.18, 95% CI 1.06, 1.32), but the association of artificially sweetened soft drinks became statistically not significant (HR 1.11, 95% CI 0.95, 1.31). Juice and nectar consumption was not associated with type 2 diabetes incidence. CONCLUSIONS/INTERPRETATION: This study corroborates the association between increased incidence of type 2 diabetes and high consumption of sugar-sweetened soft drinks in European adults.

Comparison of fatty acid proportions in serum cholesteryl esters among people with different glucose tolerance status: the CoDAM study.

BACKGROUND AND AIM: Altered fatty acid patterns in blood may be associated with insulin resistance and related disorders. We investigated whether serum proportions of cholesteryl fatty acids and desaturase activity are associated with glucose tolerance status and insulin resistance. METHODS AND RESULTS: Data were obtained from a cross-sectional study among 471 Dutch participants aged ≥40 years. Individual fatty acids in serum cholesteryl esters were determined and endogenous conversions by desaturases were estimated from product-to-precursor ratios. Proportions of fatty acids were compared among participants with normal glucose tolerance, impaired glucose metabolism and newly diagnosed type 2 diabetes. Partial Spearman correlation coefficients between fatty acids and homeostasis model assessment-insulin resistance (HOMA-IR) were calculated. Adjustments were made for lifestyle and nutritional factors. The proportions of total saturated, mono-unsaturated, trans- and poly-unsaturated fatty acids did not differ significantly between groups, but several individual fatty acids did; the proportions of C18:0 and C20:3n6 were higher, whereas those of C18:1n7 and C20:4n6 were lower in participants with type 2 diabetes compared with those with normal glucose tolerance. Activity of Δ5-desaturase, that is, ratio of C20:4n6 to C20:3n6, was lower (p < 0.01) in participants with type 2 diabetes (7.4) than with normal glucose tolerance (8.4). HOMA-IR was correlated positively with Δ9-desaturase activity (r = 0.11, p < 0.01) and inversely with Δ5-desaturase activity (r = -0.21, p < 0.01). CONCLUSION: The observed lower Δ5-desaturase activity in participants with type 2 diabetes and its inverse association with HOMA-IR suggest that changes in fatty-acid metabolism may play a role in the aetiology of type 2 diabetes.